A roof flashing is often placed around discontinuities or objects which extend through or from the roof of a building in order to deflect water away from seams or joints. For example, a roof flashing is often used to prevent rain water from leaking about a pipe protruding from the roof. Modern roof flashing may be metal, rubber or other waterproof synthetic materials that are shaped to meet a specific need.
A typical roof flashing for a pipe has an extension that fits snuggly about the pipe and where the extension has a downward taper away from the pipe and a base that is approximately perpendicular to the pipe, for attaching the flashing to roof decking. Caulking is sometimes used around seams formed where the pipe flashing material contacts the pipe or decking to ensure water does not leak through the roof of the structure and into the building protected by the roof.
There are roof flashings for metal roofing. The roof flashings for metal roofs have extensions through which pipes or other objects can extend, as described hereinabove. In addition, the roof flashings have a small flange-like base that extends from bottom of the extension for attaching the roof flashing to the metal roof. There are some metal roof flashings that have an opening that extends the entire length of the extension for wrapping the roof flashing around the pipe or the object before it is attached, via the based, to the metal roof. Caulking can then be used around the base to where it attaches to the metal roof and around the opening through which the pipe or object extends in order to mitigate or prevent leakage. One such roof flashing is described in U.S. Pat. No. 5,176,408.